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(: Test: K-DateAddYMD-3                                  :)
(: Written by: Frans Englich                             :)
(: Date: 2007-11-22T11:31:21+01:00                       :)
(: Purpose: The '-' operator is not available between xs:yearMonthDuration and xs:date. :)
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xs:yearMonthDuration("P1Y") - xs:date("1999-08-12")